V-belt with small grooves on underside



A118; 1940- A. L, FREEDLANDER V-BELT WiTH SMALL GROOVES 0N UNDERSiDE Filed June 4, 1938 3 Sheets-Sheet l ABRAHA LfREEDL/INDER,

Aug. 6, 1940. A. L. FREEDLANDER V-BELT WI TH SMALL GROOVES 0N UNDERS'IDE Filed June 4 19:58 3 Sheets-Sheet 2 Aug. 6, 1940. A. L. FREEDLANDER V-BELT WITH SMALL GROOVES ON UNDERSIDE Filed June 4, 19325 5 Sheets-8heet s 9 I8 [9 20 2 Jm v ABRAHAM I,FKEEDLANDER,

- PM: A... 5, 1940 2,210,073

UNITED STATES PATENT mm V-BELT WITH SMALL GBOOVES ON I UNDERSIDE Abraham L. Freedlander, Dayton, Ohio, assignor to The Dayton Rubber Manufacturing Company, Dayton, Ohio, a corporation of Ohio Application June 4, 1938, Serial N0. 211,909 4 Claims. (Cl. 74-233) My invention relates to belts and in particular can flow from the area of compression tothe areas to V-belts. of separation without causing the layers of fabric It is the object of this invention to provide a adjacent the groove to project too far into the belt which can pass around a relatively small body of the belt to cause it to bulge laterally or 5 pulley easily without distortion of the rubber and otherwise interfere with its operation. 5 fabric composing the belt. It is an object of this invention to provide a It is an object to provide a belt, the underside belt preferably having zones comprising a tenof which on the compression side has molded sion section, a neutral axis section and a comtherein aplurality of transverse, spaced, relativepression section, the compression section being ly small grooves which give great flexibility to the divided into a main body section, an intermediate 10 belt, enabling it to negotiate pulleys more easily, area section, and a bottom cover section which and the outstanding feature of which is to preincludes the grooves. It wlll'be understood that vent distortion of the belt bodily in the grooves. these sections are not'physically separate neces- In this connection, there is employed in the comsarily but this belt accommodates the free moving pression section of the belt or a part thereof of-the several sections required by the mechanics 16 adjacent the grooves, transversely arranged fibers of the belt without setting up .undue heat and embedded in rubber or the like which are arwithout separation of the plies. The belt is inranged so as to take'up the distortion of the extensible longitudinally and incompressible fabric on the bottom of the belt in which the laterally. It may be used either with or without 20 grooves are cut or molded. The advantage of a cover. In either event, it has arigid cross-wise 20 this construction lies in the fact that the fibers structure, is easily bendable without deformation, are cross-wise parallel to the grooves, so that and is longitudinally inextensible. each groove pushes itself, so to speak, up between Referring to the drawings: a the fibers, when the belt passes over a pulley. Figure 1 is a side elevation of the belt mounted 5 The same result occurs without fibers. but the upon a driving and driven pulley. lateral compressibility of the belt is prevented to Figure 2 is a vertical section through a mold a greater degree by the employment of the fine showing the belt inelevation to indicatehow the transverse fibers. Such an arrangement of fibers grooves are molded in the base of the belt after is preferred, but I do not mean to exclude fibers it has been built but before it is vulcanized in promiscuously mixed in this compression area in the mold. 30

the rubber. Figure 3 is a bottom plan view of the belt with It is a further object of this invention to prothe grooves exaggerated in size. The grooves vide a belt having these small grooves on the may be transverse at right angles to the axis of underside, the lower layers of the belt adjacent the belt or at an angle thereto.

the grooves being formed of rubber and fabric, Figure 4 is a longitudinal section 'on the line 35 the layers of fabric following the' contour of the 4-4 of Figure 3. grooves. In this combination I prefer to pro- Figure 5 is a section on the line 5-5 looking vide a resilient area intermediate these layers of in the direction of the arrows of Figure 1 showing fabric adjacent the grooves and the main body the constructionof the belt transversely.

40 of the belt so that any deformation due to the Figure 6 is a modified form of the belt shown 40 deepening of the grooves as they pass around a in cross section illustrating in detail the arrangepulley will result in a displacement of the interment of the transverse parallel fibers in the commediate area of rubber without disturbing the pressible section adjacent the covering layers on main body of the belt composed of layers of rubthe bottom of the belt.

her and fabric and the like. Figure '7 is a similar view taken longitudinally 5 The basic principle of this belt is to provide a through the belt. belt that will accommodate itself when bent on Figure 8 is a modified view like Figure 6 showthe underside without bulging and without dising the fibers promiscuously mixed in the comturbing the main body of the belt. pressible section.

It is a further object to so interleave layers of Figure 9 is a view similar to Figure 7 showing 50 rubber and fabric on the underside of the belt the compressible area on the underside of the adjacent the grooves that when the belt is bent, belt formed with grooves and formed of four the layers will tend to separate at the mouth of layers of fabric material. the groove and compress at the top of the groove Figure 10 is a similar view showing a modified 65 so that the rubber between the layers of fabric form of construction of the belt in which the the edges of the grooves between the layers of fabric.

Figure 12 is a similar view with the belt in a horizontal position before it passes over the pul ley.

Referring to the drawings in detail, the belt preferably of V shape in cross section, is mounted in the V groove pulleys 2 and 3. This belt is formed of a plurality of layers of rubber'and fabric, either straight laid or bias laid, and said layers of rubber and transverse fibers are wrapped with layers of rubber and fabric. It is then placed in a mold 4 which has small transverse ridges 5 in the bottom thereof. It is there molded and vulcanized in molded conditions so that when it is taken out of a mold, it consists of a top 6, sides 1 and 8, and a bottom 9 having transverse grooves it]. These grooves are relatively shallow. and are molded in the bottom of the belt.

As will be seen in Figure 4. when the grooves reach the place where the belt is bent in passing over a pulley, the lower edges ll of the groove approach one another and the upper portion of the groove at l2 projects into the belt while the groove narrows.

Referring to the construction of the belt, it may be built of a variety of different types of textile materials and of rubber or synthetic rubbers or synthetic resins. When I refer to rubber, I comprehend within that term such equivalent materials.

The belt consists of a plurality of superimposed layers of fabric 13 which are impregnated with rubber and have rubber layers l4 therebetween. Those layers at approximately l5 may be either of fabric or cords and constitute the strength band to make the belt inextensible longitudinally. One or more layers l6 are preferably laid on top of the strength band to form a tension area. The compression section is designated at II. It consists of a plurality of layers of compressible fabric and rubber under which is an inner area 18 of rubber having parallel fibers l9 arranged transversely'of the belt. This area i8 is transversely incompressible but it is capable of receiving the deformed grooves in the cover layers as hereinafter described. The cover preferably consists of two layers of fabric 20 embedded in rubber 2 I. It is in these layers that the grooves it! are molded. This construction can be seen more clearly in the enlarged sections 11 and 12. In Figure 12 the belt is in straight condition. The grooves are of their normal size. The bottom layers of fabric 28 are parallel to one another and the rubber 2| tlierebctwecn is of uniform thickness. When the belt passes over a pulley. as shown in Figure 11, the groove dips and narrows. This tends to bring the layers of fabric closer together at the top of the groove as at 22 and to spread the layers apart adjacent the bottom edges of. the groove as at 23. Thus the rubber 2| can fiow from the point 22 to the point 23, instead of projecting upwardly at 22 into the intermediate area l8.

In some instances this upwardly projecting movement does take place, as will be seen in Figure 4, and it is for that reason that the inner area l8 of yieldable material that is preferably transversely incompressible, is formed in the belt because any deformation of the grooves l into the area l8 will simply displace a portion of the rubber of this area without interfering with the main body of the belt in the general areas l4, l and H.

In Figure 8 the fibers l9 are mixed in all directions. In Figure 9 there are four layers of wrapper, which give a sufficient depth to cushion the movement of the groove without disturbing the main body of the belt, that is, without disturbing the compression section II. In Figure both the intermediate section I8 and the compression section H are made up of a homogeneous body of rubber and transverse fine fibers superimposed upon a two-layer wrapper.

It will be understood that by reference to the tension, compression and neutral axis sections, is meant those sections of a belt into which the belt naturally divides itself, even though there may be no physical demarcation between these sections when the belt is visibly inspected.

It will be observed, therefore, that the belt consists of the wrapper layers in which the grooves are formed; an intermediate cushioning area, and the main body of the belt, which is preferably formed of a compression section, a strength band or neutral axis section, and a tension section. As heretofore stated, these sections are not clearly defined, different areas, but such sections are those into which the belt tends to arrange itself as it passes over the pulleys, and in recognition of that fact, the belt is built preferably of different materials in the different sections so that the strength band will be relatively inextensible longitudinally while the tension and compression sections will be laterally incompressible but are longitudinally stretchable or compressible as the case may be.

It is highly desirable that the line between the intermediate area on its top and the main body of the belt be substantially straight and that this area be suinciently deep to permit of deformation by the grooves when the shape of the grooves changes without disturbing the main body of the belt.

The advantage of this arrangement over the prior art is that heretofore very large grooves were formed in the belt on the underside which extended into and through the compression section, thereby weakening the belt and setting up various problems such as cracking adjacent the grooves, separation of the compression section from the belt,'etc. In some instances considerable heat was developed by reason of these movements. The total side area of the belt was correspondingly reduced, which was an undesirable characteristic in some types of belts.

The present arrangement completely eliminates any disturbance of the main body of the belt; the maximum side area of the belt is maintained; and by having a plurality of very small grooves. a much larger total area for compression is obtained than With a relatively few large molded or cut-through teeth heretofore used in the art.

By the term groove I mean a relatively shallow, small transverse depression on thrunderside of the belt as distinguished from large cut-away portions in the prior art belt which form teeth of large dimensions on the underside of the belt.

It will be understood that I desire to comprehend within my invention such modifications as come Within the scope of the. claims and the invention.

Having thus fully described my invention, what I claim as new and desire to secure by Letters ber and transversely arranged fibers,- and a sec- Patent, is:

1. In combination, in a belt, of a main body portion comprising a tension, neutral axis and compression section, an under section, a grooved section mounted beneath the under section, the

grooves in the last-mentioned section being substantially semi-cylindrical and extending up into the under section of the belt, and means for reinforcing said under section whereby deformation of the walls of the grooves is accommodated without distorting the main body portion of the belt. 5

2. In combination, in a belt, of a belt body comprising a tension, section, an under section, a grooved section mounted beneath the under section, the grooves in the last-mentioned section being substantially semi-cylindrical and extending up into the under section of the belt, and means for reinforcing said neutral axis and compression whereby deformation of the walls of the grooves is accommodated without distorting the main body of the belt.

3. In combination, in a belt, of a main body portion comprising superimposed layers of textile material and rubber, an under section of rubtion'on the under side of the belt having substantially semi-cylindrical grooves extending up into the under section of the belt and molded therein transversely of said belt, whereby deformation of the walls of the grooves is accommodated without distortion of the main body of the belt.

4. In combination, in a belt, of a main body portioncomprislng superimposed layers of textile material and rubber, an under section including reinforcing'means, and a section on the under side of the belt having substantially semi-cylindrical grooves extending up into the under section of the belt and molded therein transversely 0t said belt, whereby deformation of the grooved walls is accommodated without distortion of the ,said main body portion of the belt.

ABRAHAM L. FREEDLANDER. 

